Internal-combustion engine.



C. A. SAWT ELLE. LNTERNAL COMBUSTION ENGINE.

APPLICATION FILED OCT-1.7.1912.

Patented Oct. 17, 1916.

3 SHEETS-SHEET 1.

wi lme/ooeo C. A. SAWTELLE.

INTERNAL comsusnou ENGINE.

APPLICATION FILED OCT-17,1932.

Patented Oct. '17, 1916.

.3 SHEE[SSHEET 2.

r E A\\\ Gttowuga C. A. SAWTELLE.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED OCT-17.1932.

k 6 d 1 M w 1w a ZN 4 U L E 7 d w fla 2 m e m 3 C m G Howey To all whom it may concern CHARLES a. SAWTELLE, or DAYTON, 01-110.-

Specification of Letters Patent.

.IN'rERnAL-ooMBiIsmoN ENGINE.

Patented. Oct. 17, 1916.-

y .o I Application filed October 171 1912., Serial No. 726,197;

Be. it known that I, CHARLES TELLE, a citizen of the United States, residginesof the two cycle type'.

- provide means to quickly and efliciently exing at Dayton," in the county of Montgomery and State of Ghio, haveinvented certain new and useful Improvements in Inte'rnal-Gombustion"Engines, of which the following is a specification, reference being hadtherein to the accompanying drawing.

This invention relates to internal combustion engines and more particularly to an The primary ob ect of the mvention is to haust the burnt gases from the cylinder and introduce a fresh mixture therein.

To this end it is a further object to provide the cylinder with a large exhaust port near the lower limit of the stroke of the piston; to provide means to inject the fresh mixture into the cylinder at a point above the exhaust port; a'ndfio cause the inlet port to be openedv and closed within the brief interval during which the edge of the pis-. ton is below the-exhaust port.

Another object of the invention is to pro.- vide means whereby a light charge of the explosive mixture may be introduced into the cylinder and prevented from mingling with the burnt gases before it is ignited, thereby enablingthe engine to be throttled I to a low speed.

. admit the explosive mixture through the Other objects of the invention are to piston; to provide a large exhaust port; to

introduce the explosive mixture into the crank-case through the shaft bearing and to adequately control the .introductlon thereof; and to'so construct and or anize,

the engine as a whole as to provide a simple, positively operated mechanism WhlOh will permitthe movements of theparts to be properly timed.

In the accompanying drawlngs, Figure 1 is a vertical, sectional view, takenthrough the crank casing and one cylinder of an,

engine embodying my invention F igs. 2, 3

Yand v4 are detail views taken through the cylinder showingthe several parts of the mechanism in successive posltions; Fig. 5

' is a sectiontaken on the line a: w of Figf-l and-Fig. 6 is a section taken through the intake bearing of the shaft.

In these drawings I have illustrated one embodiment of my invention and have shown the same as comprising a cylinder 1,

manner.

of the water jacket type, mounted upon a I I base 2 and having an inclosed crank casing 3 into which the explosive mixture is drawn and compressed in the usual manner, although it will be understood that the compression ofthe-mixture may be secured in any suitable manner.- Mounted within the crank casing is the usual crank shaft 4 having a wrist pin 5 on which is mounted a connecting rod 6, the upper end of which is connected with the piston 7 which is mounted within the cylinder -1 and is of the trunk-piston type. As is usual in two cycle engines the exhaustion of the burnt gases from the cylinder takes place during the lower portion of the power stroke of the piston and the fresh explosive mixture is introduced into the cylinder under pressure and thus serves to not only charge the vcylinder for another explosion but to assist in scavenging the cylinder, that is, forcing stance, however, I have so arranged the parts that this is effected in a very eflicient To accomplish this the fresh mixout the, burnt gases. In the present'inture is introduced through the main piston extend substantially about the entire cir-' cumference of the cylinder. The fresh mixture is introduced through a central passageway or supplemental cylinder 9 formed.

in the main plston 7, preferably by securing the upper end of the supplemental cylin der within a central opening in the piston' head, thus leaving both the innerand outer walls of the supplemental cylinder clear for the operation of thecontrolling parts, as

hereinafter described. In order that the fresh mixture. may be introduced at a point above the exhaust passage I have made the piston of such alength that its extreme upper end will lie at 'a point above the plane of the exhaust port when .the piston is in its lowermost position and have then cut away or beveled the edges of the piston, as indicated at 10,,to connect; the exhaust port with the main cylinder when the main piston is in its lower position. In this manner I 'am, as above stated, enabled to place a large exhaust port near the lower limit of the stroke of the main piston and thus utilize the full power of the explosion and fur- 14 which may be moved into and out. of

ther, when the piston has moved downward a distance sufficient to cause the side walls thereof to clear the exhaust port-the burnt gases will exhaust quickly through the port 'and the fresh mixture will be introduced into the central part of the cylinder at a point above the exhaust. port.- This mixture being introduced under pressure will pass upward through the central part of' the cylinder and coming in contact with, the cylinder head will be deflected and caused to move downward along the .side walls of the cylinder, thus forcing the burnt gases down and through the exhaust port. The

action is such that there is very little tendency on the part of the fresh mixture to mingle with the burnt gases. This action takes place while the main or power piston is at substantially the lowermost limit of its stroke and as this piston moves upward to again close the exhaust port the burnt gases will be further expelled from the cylinder,

thus making the exhaustion of the burntgases very complete.

- The admission of this fresh mixture through the supplemental cylinder 9'may be accomplished and controlled in any suit- I able manner. In the present instance I have shown the supplemental cylinder as having inlet ports 11, there being several shown in the, present drawings, but the number being optional. It will be noted that when these ports are open they will connect the supple mental cylinder with the intefior of the main piston which is 1n open communication with the compression crank case. Consequently, the compressed mixture in the crank case will pass through the ports,

through the supplemental cylinder 9 into the main cylinder 1. The cylinder may be' provided with devices of any suitable kind to control the inlet portsN In the present construction I have utilized a supplemental piston 12 which is mounted within the supplemental cylinder and is adapted to move across the inlet port or ports to close them and to be moved downwardly a distance sufficient to clear these ports and connect the crank case with the main cylinder. Cooperating with the supplemental piston is a slidable member 13 which is here shown in the form-of a sleeve mounted on the exterior of the supplemental cylinder and having movement relatively to this cylinder and to the supplemental piston, the relative movements of the supplemental piston andthe sleeve serving to control the admission of the compressed mixture through the ports '11 of the supplemental cylinder, the sleeve being in theprese'nt instance provided with ports alinement with the ports 11. The movements of the supplemental piston and'its copor a cross piece 18*.

opegating sleeve are so timed that the inlet. 11 of-the supplementalcylinder will beopened after the upper edge of the side Wall of the main piston has cleared the exhaust port 8 and will be" closed at the very beginning of the upward stroke of the piston.

These movements are preferably controlled by suitable connections with the crank shaft and these connections are such that a very I short movement of the crank while it is in its inner or lowermost position, where it imparts a minimum of movement to the piston, will first open and then-close the inlet ports.

The supplemental piston 12 is preferably "rod 6 for the 'main piston. An-arm 18 is pivotally connected at its upper end with the sleeve 13 and at its lower end with one arm 19 of a bell crank lever mounted on a stud 20 carried by the lower portion of the main piston 7. The other arm of the bell crank lever extends upwardly, as shown at 21, and has secured thereto a link 22 which is pivotally connected at its opposite end ,,to

the connecting rod 6. Obviously, the, movement of the connecting rod 6 will cause the bell crank lever 1921 to move about its axis, thereby imparting vertical movement to the sleeve. The arrangement of the parts is such as to properly time the movement of the sleeve with relation to the main piston andthe supplemental piston. There may be one or more of the arms, 18, preferably there is one on each side of the supplemental cylinder and they lie between the connecting rod 6 for the main piston and the side walls of this piston. their cooperating parts may be of any suitableconstructiom Those here shown were designed to provide the necessary clearance.

It will be noted that the connecting rod 6 is in two parts, joined near their upper ends by a transverse barf (only one part of the rod being here shown), and the connecting "rod' 15, for the supplemental, piston, is ar-- ranged between the two parts of the connecting rod .6, while the arms l8'are offset to clear the latter rod and are connecte d'by It will be apparent that the operation "of The connecting rods and the crank shaft and the main. piston will impart movement to the supplemental piston and the sleeve 13; This "movement-is such that'when the main piston is in its I outermost position, that is, the position which it occupies when the explosion takes,

place, the supplemental. piston willbe in its outermostposition and will extend across the. inner ends of the inlet ports. Thus the "supplementalpiston becomes a part of the main piston and "receives'a portion of the force of theexplosion; Inasmuch as this piston extends across the inlet ports the sleeve is not subjected to any portion of the.

force of the explosion; Fig.1 of the drawings shows the parts'in this position, the o main piston being there shown as. just be ginning its inward movement. As the maln piston moves inward the supplemental piston and thesleeve move inward therewith, but the movements of the supplemental p1ston and sleeve relatively to the supplemental cylinder are such that the inlet port will be closed by the outward movement of the sleeve before the supplemental piston has haust portand immediately thereafter opens the inlet port.- The position of the parts 1 willbe noted in Fig. 3 in which the main piston is shown as having just cleared the exhaust port and the inlet port is shown as p 80 wide open, thus permittingthe free ontrance o f-theicompressed mixture into the main cylinder. The. main piston is here v shown as in substantially its innermost position and as the crank shaft swings across its center to begin the outward movement there is very little movement on the part .of the main piston but. this action of the I crank shaft causes the sleeve 13 to move inward and close the inlet port. It will be ,40 noted that the inlet port is closed very quickly, the movement of the sleeve being accomplishedby a very short movement of the crank shaft and this movement-of the crank shaft being during that portion of its revolution when its movement has little effect upon the main piston,

It will be noted that when the parts are in the position shown in Fig.4 the inlet ports are closed and the supplemental pis- 0 ton is win the lower portion of the supplemental cylinder, thus affording. additional spacelwithin the main cylinder to'receive v the explosive mixture. As the main piston moves outwardthe supplemental piston not only moves outward therewith but moves outward relatively thereto, thereby accomplishing' an additional compression of the mixture in the main cylinder. .Heretofore much difficulty/has been ex- '60 .perienced in throttling down a two cycle engine, this being due in large partto the tendency of the fresh .mixtureto mingle with the burnt gases in the. cylinder. only a-small charge of the fresh mixture was introdu ced into the cylinder there would :very accurate control for the admission of the remain ti proportionately large amount of I burnt gases with which the fresh mixture would mingle, thus very materially reducing, if not entirely destroying, itsexplosive V qualities. It will be noted that in the present engine the supplemental cylinder forms a pocket through which the fresh mixture must pass to enter the main 'cylinder. When a small, charge of the fresh mixture is introduced-into theflcylinder a large part ofit willremain in the supplemental cylinder or pocket and will be compressed therein, thus preventing its mingling to any material extent with the burnt gases in the main cylinder. By a suitable arrangement of the. spark plug this charge can be ignited within the supplemental cylinder and thus the full. explosive force ofthe mixture utilized. In this manner the desired amount of fresh mixture can be introduced into the engine and it can be I throttled down to the desired extent. The spark plug maybe'arranged in any mannerwhich will enable the spark to ignite the fresh mixture within the supplemental cylinder when the upper portion of the main cylinder contains burnt gases. In the form of the engine here shown the spark plug-is mounted centrally in the head of the main cylinder and projectsdownward to such an extent that the spark will be formed within or very close to the lowerend of the supplemental cylinder.

It will be noted that the arrangement of the. supplemental piston within the supplemental cylinder is such that this supplemental piston receives the force of the explosion and further that it closes the inlet ports and thus prevents the force of the explosion passing through these ports and coming in contact with the sleeve on the outer side of the supplemental cylinder. In this manner the sleeve is protected from in jury and the supplemental piston is caused to form apart of the main piston and to receive its proportionate share of the force of the explosion. The supplemental piston and the mainpiston are connected .to the crank shaft by-the same wrist pin, as indicated at 5, and thus the-force of the explosion will be exerted squarely upon the crank. 1

shaft and will be utilized to the fullest extent.

As has been stated the explosive mixture may be introducedfinto the crank case and one of-the bearings for the crank shaft and 1 to control the admission of the mixture by the movement of this shaft. 5

" In Fig. 6 of the drawings I have illus-' 'trated a construction of bearing and shaft by means of which this maybe accomplished and which will afford a very adequate-and nicates with a source of supply-for the explo sive mixture, such as the carbureter.

The shaft 4 is provided on each side thereof with a radial port 26, each of which is adapted to be moved into alinement with the port of the bearing once during each revolution of the shaft 4. These radial ports communicate with longitudinal passages 27 formed in the shaft4, extending beyond the ends of'the bearings and communicating with the interiors of the respective crank-cases. The arrangement of the ports 26 in the shaft is such that the inlet port 25 will be in communication with the crank-case of each cylinder during the outward movement of the piston for that cylinder. Thus, the piston will serve to draw intoithe crank case a quantity of explosive mixture and the return or inward movement of the piston will serve to compress this mixture in the crank-case.

To prevent leakage of'the mixture about the bearing I have provided a special'packing which is very eflicient. That portion of; the engine shaft 4 which extends through the bearing is provided near its ends with annular flanges 28 which extend beyondthe brassl or other material 29 which forms the, bearing surface for the bearing and fits snugly within the metalshell or body portion of the bearing s 24, the brass 29 being slightly shorter than the shell of the bearing so as to form recesses to receive these flanges. At each end of the bearing an annular recess 30 isformed be tween the brass and the shell of the bearing and in each recess ismounted a ring 31, preferably of metal, whigh fits snugly against the corresponding flange 28, the engaging sur faces being ground if desired. A second ring 32 is mounted in each recess 30 and between the two rings is a ring of compressible packing 33. Means are provided for'exerting a pressure on the ring 32 which will not only force the outer ring 31 into engagement with the corresponding flange on the shaft, but

will also compress the packing ring and cause theinner and outer peripheries of these rings to bear tightly against the brass and shell of the bearing, respectively. The pressure on eachring .32 is preferably secured by means of a series of coiledsprings 34 which are interposed between the corresponding spring anda fixed part of the hearing which is here shown as a portion 35 extending inwardly from the shell of the bearing.

While I have shown and described one embodiment of the invention'it will be understood that this has been chosen for the purposes of illustration only and that I do not with the crank case, and means to control the communication between said supplemental.

cylinder and said crank case.

2. In an engine, a main cylinder communicating with an exhaust passage, a closed crank case communicating with, a-source of gas supply, a main piston, a supplemental cylinder carried ,by said main piston and communicating withisaid main cylinder and with said crank case, and means comprising a supplemental piston to control the communication between said supplemental cylinder and said crank case. v

3. In an engine, a main cylinder communicating with an exhaust passage, a main piston, a supplemental cylinder carriedby said main piston and communicating with said main cylinder and with a source of fluid supply, a supplemental piston mounted in said supplemental cylinder, and a part cooperating with said supplemental piston'to control the communication between said supplemental cylinder and said source of supply.

, 4. In an engine, a main cylinder communicating with an exhaust passage, a main piston, asupplemental cylinder carriedby said mainpiston and communicating with said main cylinder and with a source of fluid supply, a supplemental piston mounted in said supplemental cylinder, and a sleeve cooperating with said supplemental piston to control the communication between said supplemental cylinder and said source of supply.

5. In an engine, a main cylinder communicating with an exhaust passage, a main piston, a supplemental cylinder carried by said main piston, communicating with-said main cylinder and having an inlet 'port, and parts cooperating with each other and with said supplemental cylinder to control said inlet por v I 6. In an engine, a main cylinder communicating with an exhaust passage, amain piston, a supplemental cylinder carried by said main piston, communicating with said \main cylinder and having an inlet port, and cooperating parts to control said inlet port, said parts being mounted within and without said supplemental cylinder, respectivelyi 7. In an engine, a main cylinder compiston, a" supplemental cylinder carried by piston.

saidmain piston, communicating with said main cylinder andhaving; an inlet port," and cooperating devices'to open said inlet-port .on one stroke of s'aidmam piston and to close it on the next stroke of said main 8; In anfengine, a main cylinder commu icating with an'exhaust passage, a main 'piSl 11,-asupplemental cylinder carried by said main piston, communicating with said ofvthe outward stroke of said main piston. '9. In an engine, a main cylinder coin.- municating with an exhaust passage, a mam -main cylinder and having an inlet port, and

means to open said inlet port as the main piston ,nearsjthe .end of its inward stroke and to close said inlet port at the beginning piston,' a supplemental cylinder carried by said main piston, communicating with said main-cylinder and having 'Qaninlet port, a supplemental piston mounted within said supplemental v cylinder, and, a device cooperating with said supplemental piston to control said inlet port, said .supplemental "piston being adapted to have its head interposed between said device and said main cylinder to protect said device from the force of explosion in said main cylinder." 10 In 'an engine, a -ma1n cyllnder com- 4 municating with an'exhaust passage, a main pi'ston,a supplemental'cylinder carried by said'main piston, communicating with said main cylinder and having an inlet port, a supplemental piston--mounted within said supplemental cylinder and adapted to form apart of the head of the main piston and to receive a portion of the force of the explosion and having movement relatively to said main piston to open and close said in-" -let port in said supplemental cylinder, a

sleeve cooperating. with said "supplemental piston to control said inlet port, and means for causing said supplemental piston and i said sleeve to 'move'with said main piston and to have movement relatively thereto.

11. In an engine,- a main cylinder com- "municating with angexhaust passage, a main 1 piston having an openingingthehead there:

of, a'supplemental cylinder in said opening, having communication with the main .cylinderand also'having an inlet port communicating with the source" of fluid supply,

the wall of said supplemental cylinder being spaced away fromthe inner walls of saidv v main piston, a supplemental p'iston mounted within said supplemental cylinder, and a sleeve mounted' on the exterior of said supplemental cylinder. *and-having a port adapted to be m'ovedintoand' out-of alinemcnt with said inlet'portf.

v 12. In an eng1ne,i;a"ma1ncylinder communicating witli anexhaust passage and having an inclos'edcrank case, a main pisston mounted within said cylinder compris-f;

- .charge in said pocket.

'ing ahead and a cylindrical extension, 7.4a?

supplemental cylinder in the head"of'-said' tension of saidmain piston, said. 'supple j a port adapted tobe moved into "and out of alinement with said inlet port, and-means for imparting-movement to said supplemen- ,7 i 13. In an englne, a maln cylinder comtal piston and said sleeve.

municating with an exhaust passage, a main piston having an inlet passage therein com- -municat1ng with said main cylinder and forming a pocket, means cooperating with .said main piston to compress the charge in said pocket, and means for exploding said 14. In an englne, a mam cylinder communicating with an exhaust passage,'a main piston having an inlet passage therein communicating with said main cylinder and forming a pocket, a piston mounted in said passage'and cooperating with said main'piston to compress the charge in said pocket, and a spark plug mounted in substantial alinement withsaid pocket. 7

15. In an engine, a main cylinder. commun'icating with an exhaust passage, a main piston, a supplemental cylinder carried by said main piston and communicating with. said main cylinder and with a source of fluid supply,; and means cooperating with said main piston to control the communication between said supplemental cylinder and said source of supply and to cause a supplemental compression of the fluid Within said supple- 1 mental cylinder 16. In an englne, a main cylinder com- -municating with an exhaust passage, a main piston, a supplemental cylinder carried by said main piston and communicating with said-main cylinder and with a sourceof'fluid supply, and a supplemental piston mounted in said supplemental cylinder, and means to cause said supplemental piston'to move forward relatively to said main piston-during j the compression stroke of said main piston.

-17 In an engine, a main cylinder com-.

municating with an exhaust passage, a main piston, a supplemental cylinder carried by]..-

"said main piston and "communicating" with said main cylinder and with a source of fluid supply, a supplemental piston mounted in said supplemental cylinder, meansto cause said supplemental piston to move forward-relatively to said mamplston dur' the compression stroke of said main piston,

an :a spark plug-mounted on the head of a, sai main cylinder and arranged to pro ect' 1 30 into said supplemental cylinder when said main piston is in its outermost position.

18. In an engine, a, main cylinder, a main piston, a supplemental cylinder carried by said main piston and having a port, a supplemental piston mounted in said supplemental cylinder, a crank shaft, connecting "port, a crankshaft, and devices connecting said main piston, said supplemental piston and said sleevewith said crank shaft to cause said parts to move inunison and to cause ,said supplemental piston and said sleeve to have movement relatively to said main piston.

20. In an engine, a main cylinder communicating with an exhaust passage,'a main piston, a crank shaft,'-a connecting rod connecting said main piston with said crank shaft, a wrist pin carried by said crank shaft and serving to connect said connecting rod thereto, a supplemental cylinder carried by said main piston, communicating with said main cylinder and with a source of fluid supply, a supplemental piston mounted in said supplemental cylinder, a connecting rod connected with said supplemental piston, an eccentric mounted on said wrist pin, and a strap connecting said lastmentionedconnecting rod with said eccentric.

21. In an engine,'a main cylinder communicating with an exhaust passage, a main piston; a crank shaft, a connecting rod connecting said main piston with said crank shaft, a supplemental cylinder carried by said main. piston and communicating with said main cylinder and with a source of fluid supply, a supplemental piston mounted in said supplemental cylinder, means to move said supplemental piston relatively to said 'main piston, a sleeve mounted on said supplemental cylinder, a lever mounted on said mam piston, a connectlon between said le-' ver and said sleeve, and a connection between said lever and the connecting rod for said main piston.

22. In an engine, a main cylinder com- -municating with an exhaust passage, a main piston, a crank shaft, a connecting rod. connecting said main .piston with said crank shaft, a wrist pin carried by said crank shaft and serving to connect said connecting rod thereto, a supplemental cylinder carried by said main piston, communicating with said main cylinder and with a source of fluid supply, a supplemental piston mounted in said supplemental cylinder, a connecting rod connected with said supplemental piston, an

eccentric mounted on said wrist pin, a strap A connecting said last-mentioned connecting rod with said eccentric, a sleeve mounted on said supplemental cylinder, abell crank 1ever mounted on said main piston, a connecting rod connecting one arm of said bell crank lever with said sleeve, and a link connecting the other arm of said bell crank lever with the connecting rod for said main piston.

23. In an engine, a cylinder, and'a piston mounted therein, one-ofsaid parts having an exhaust port and one of said parts having an inlet port, said exhaust port being adapted to be open when said piston is at the inner limit of its movement, a crank shaft, a connection between said crank shaft and said piston, and means controlled by the movement of said crankshaft across its central position, whensaid piston is in its innermost position, to open and close said inlet port.

- 24:. In an engine, a cylinder, and a piston mounted therein, said cylinder having an exhaust port arranged near the inner limit of movement of said piston and adapted to be open when said piston. is in its innermost position, said 'ipiston' having an inlet port, and operable means carried by said piston for opening and closing said port, a

crank shaft, a connection. between said crank shaft and said piston, and means actuated by the movement of the crank of said shaft transversely to the line of movement. of said piston, when the piston is in its innermost I position, to actuate said operable means for opening and closing said inlet port, whereby the opening and closing of said port take place while said piston is substantially stationary.

In testimony whereof, I afiix my signature in presence of two witnesses.

CHAS. A. sAw'rELLn Witnesses:

JOSEPH T.- M Par, HARRIET L. U I M-MAKER: 

